Semi-automatic handguns having integrally molded polymeric frames that typically have a generally hollow handgrip, the major portion of which provides a chamber used to accommodate a magazine. The remaining portion is in the form of a downwardly opening cavity located rearwardly of the magazine chamber. Other than certain advantages that accrue during the molding process, such as a substantial reduction in the amount of polymer needed to mold the frame and the ease in removing the frame from the mold in which it is formed, the cavity serves no useful purpose in the gun, per se. In its appearance as well as in the use of the gun, however, the open cavity is generally considered to be a serious drawback both from the standpoint of their appearance and operation and various means have been proposed to overcome such drawbacks.
U.S. Pat. No. 5,052,140 discloses a magazine guide which attaches to the butt of the handgrip to aid with the insertion of the magazine into the handgun. Additionally, a plug is fitted into the open cavity behind the magazine cavity.